Abraham must feel quite surreal as he hears God's intent and proceeds to see two of his guests arise and embark to carry out the mission. He realizes that he has hosted the very destroyers of Sodom. His nurturing of these destroyers and their circuitous pit stop at his tent may symbolically represent Abraham's nurturing of Sodom's treachery. Abraham's complicity in Sodom's treachery may be attributed to his allowing Lot to depart from his company earlier in favor of encamping at Sodom (13:8-14) as well as Abraham's failure to seize control and reform Sodom after his successful campaign to free Lot from the four kings (14:15-24). As such, God is now turning to Abraham to demonstrate the results of his actions and inaction. Abraham's contemplative overlook at the destruction the morning after his failed attempt to save the cities (19:27-28) crushes him and Abraham is too pained with the memories of his failure in Hebron and decides to travel in a southerly direction and moves to Gerrar to open a new chapter in his life (and perhaps to see if Lot survived) (20:1).1-----
1 - Gad Dishi, "Saving Zoar: How Did Lot Succeed?", Jewish Bible Quarterly 38, no. 4 (October-December 2010), 218, n. 7.